public function __construct($rawData,$config=array())
{
    $this->rawData=$rawData;
    foreach($config as $key=>$value)
        $this->$key=$value;
}

protected function calculateTotalItemCount()
{
    return count($this->rawData);
}

protected function fetchData()
{
    if(($sort=$this->getSort())!==false && ($order=$sort->getOrderBy())!='')
        $this->sortData($this->getSortDirections($order));

    if(($pagination=$this->getPagination())!==false)
    {
        $pagination->setItemCount($this->getTotalItemCount());
        return array_slice($this->rawData, $pagination->getOffset(), $pagination->getLimit());
    }
    else
        return $this->rawData;
}

protected function fetchKeys()
{
    if($this->keyField===false)
        return array_keys($this->rawData);
    $keys=array();
    foreach($this->getData() as $i=>$data)
        $keys[$i]=is_object($data) ? $data->{$this->keyField} : $data[$this->keyField];
    return $keys;
}

protected function getSortDirections($order)
{
    $segs=explode(',',$order);
    $directions=array();
    foreach($segs as $seg)
    {
        if(preg_match('/(.*?)(\s+(desc|asc))?$/i',trim($seg),$matches))
            $directions[$matches[1]]=isset($matches[3]) && !strcasecmp($matches[3],'desc');
        else
            $directions[trim($seg)]=false;
    }
    return $directions;
}

protected function getSortingFieldValue($data, $fields)
{
    if(is_object($data))
    {
        foreach($fields as $field)
            $data=isset($data->$field) ? $data->$field : null;
    }
    else
    {
        foreach($fields as $field)
            $data=isset($data[$field]) ? $data[$field] : null;
    }
    return $this->caseSensitiveSort ? $data : mb_strtolower($data,Yii::app()->charset);
}

protected function sortData($directions)
{
    if(empty($directions) || empty($this->rawData))
        return;
    $args=array();
    $dummy=array();
    foreach($directions as $name=>$descending)
    {
        $column=array();
        $fields_array=preg_split('/\.+/',$name,-1,PREG_SPLIT_NO_EMPTY);
        foreach($this->rawData as $index=>$data)
            $column[$index]=$this->getSortingFieldValue($data, $fields_array);
        $args[]=&$column;
        $dummy[]=&$column;
        unset($column);
        $direction=$descending ? SORT_DESC : SORT_ASC;
        $args[]=&$direction;
        $dummy[]=&$direction;
        unset($direction);
    }

    // This fix is used for cases when main sorting specified by columns has equal values
    // Without it it will lead to Fatal Error: Nesting level too deep - recursive dependency?
    $args[]=range(1,count($this->rawData));
    $args[]=SORT_ASC;
    $args[]=SORT_NUMERIC;

    $args[]=&$this->rawData;
    call_user_func_array('array_multisort', $args);
}